40. An electric motor raises a load of 0.2 kg, at a constant speed, through a vertical distance of 3.0 m in 2: the acceleration of free fall is 10 m/s2, the power in W developed by the motor in raising the load is :

(a) 0.3
(b) 1.2
(c) 3.0
(d) 6.0
41. An object is falling freely from a height x. After it has fallen a height, it will possess :
(h) only kinetic energy

In order to place a satellite into orbit, it requires enough fuel to supply the necessary mechanical energy. into what types of mechanical energy does the fuel get transformed?

Carbon-14 is a radioactive element that undergoes beta decay. which force is responsible for allowing carbon-14 to become stable? electromagnetic gravitational weak nuclear strong nuclear

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90